(d) Kinematic fit:
The uncertainty associated with the kinematic fit arises from the inconsistency of the track helix parameters between data and MC simulation.
Therefore, the three track parameters \(\phi _0\) , \(\kappa \)  and \(\tan \lambda \)  are corrected for the signal MC samples, where the correction factors are obtained by comparing the pull distributions of the control samples described in detail in Ref. [1]}.
The resulting difference in the detection efficiencies between the samples with and without the helix correction is taken as the systematic uncertainty.
